The present invention relates to the construction of waterproof systems in the mortar-bonded environment. Such environments typically include tiled floors and walls and associated fixtures and drains (e.g., in showers).
Conventional methods of installing ceramic tile shower floors have typically included several steps. First, a sloped mortar bed is installed that slopes from an edge (e.g., a wall, a curb, or some other border) to the position of a drain in a subfloor. This mortar bed is typically referred to as sloped fill, or “pre-slope”. A waterproof barrier, commonly referred to as a shower pan liner, is subsequently positioned over the sloped mortar bed and fixed to the drain. Conventional shower pan liners are not designed to bond to a substrate or to ceramic or stone tile and thus a second non-bonded (“floating”) mortar bed must be overlaid to provide a load distribution layer and bonding surface for the tile. To have sufficient strength and mass, such non-bonded mortar beds for shower floors should have a minimum thickness of at least about 1.50-inches and should be reinforced with galvanized wire mesh to comply with industry standard guidelines. This method of shower floor construction has proven over time to be reliable when properly built, but requires a high degree of trade knowledge and skill and takes considerable time to construct.
More recently, changing consumer preferences, designer influences, and in some cases the unavailability of craftsmen skilled in these techniques have driven changes in consumer preferences, and in the manner in which such showers (or equivalent structures) are constructed. In particular, the trends point toward simplified shower installation methods and systems.
To facilitate these trends, integrated systems have recently been developed that use lighter materials, and that can be installed using quicker, simplified methods. Much of this progress has been made possible with the advent of a new generation of materials that allow each layer to be bonded to the previous. Many of these materials that have been developed in recent years have incorporated fabric faces which are integrally molded onto component faces. In particular, because the relevant mortar materials mechanically lock to the open three dimensional structure of the fabric face, the fabric faces enable waterproofing membranes, drains and other components to be mortar bondable. In some cases these systems are formed of a prefabricated shower tray (typically formed of polymer foam) which is mortar bonded to the subfloor. In some typical systems, a waterproofing membrane, referred to as a load bearing, bonded waterproof membrane, is fixed to the foam tray with thin set mortar. The tile is then bonded over the membrane, again using thin set mortar. Thus, a typical integrated system could include (in order) substrate/initial mortar layer/shower tray/second mortar layer/membrane/third mortar layer/tile.
As a further convenience, a pre-manufactured flanged drain fixture can be positioned on the mortar on the tray to provide a structural location for the drain grate, to provide ample surface adhesion for the waterproofing membrane, and to connect the drain to the remainder of the plumbing. In many circumstances, the flanged drain fixture is formed to include a circular, square or rectangular flange with the drain opening in the desired location (typically the center). This flange is typically pressed against the thin set mortar on the tray and provides the necessary surface for adhering and bonding the waterproofing membrane. The flange also helps provide structural support for the final drain fixture and its grate. In a typical construction, after the flanged drain fixture is positioned on the foam tray (and mortar), another layer of thin set mortar is applied over the entire surface, following which a load bearing, bonded waterproof membrane is added. The final tile surface is added over the membrane, again using thin set mortar.
In order to provide adequate adhesion and form a water tight seal between the membrane, thin set mortar, and the flanged drain assembly, the top surface of the drain assembly has typically included an incorporated fabric layer. For a number of reasons, including conventional manufacturing techniques, the bottom of the flanged drain fixture, which likewise must be set with thin set mortar, has not included such an integrated fabric face. As a result, such drain flanges lack an adequate bonding surface between the bottom of the drain flange and to the thin set mortar that supports the drain flange assembly. Providing and maintaining support beneath the drain is nevertheless quite important because the drain area tends to experience much of the loading forces in this type of structure.
Accordingly, a need exists for a drain flange fixture that includes an integrated fabric on all surfaces (typically upper and lower) that receive or contact thin set mortar.